CLS 306 BB lecture 9

What is the average blood volume in an adult?

~10 ± 2 pints

~5 liters (5,000 mL)

What is the average blood volume in a neonate/infant (< 1 year)?

~1 pint

~500 mL

What is the normal hemoglobin (Hgb) range for adult females?

12–16 g/dL

What is the normal hemoglobin (Hgb) range for adult males?

13–18 g/dL

What is the normal hematocrit (Hct) range for adult females?

36–48%

What is the normal hematocrit (Hct) range for adult males?

39–54%

What are the three transfusion statuses?

• Routine / ASAP

• Emergency

• Refusal

What transfusion statuses are considered emergencies?

STAT (Statim) and Massive Transfusion Protocol (MTP)

What are the treatment objectives of transfusing RBCs, plasma, and platelets?

• RBCs: Correct anemia by maintaining oxygen-carrying capacity to vital organs

• Plasma: Maintain the coagulation scheme, correct coagulopathy, and support blood volume and osmotic pressure

• Platelets: Correct thrombocytopenia and maintain the clotting mechanism

What is the emergency transfusion category?

STAT (Latin: Statim — immediately, without delay)

When is STAT transfusion typically required?

When the patient has active or uncontrolled bleeding

What are common clinical scenarios requiring STAT transfusion?

• Surgery

• Trauma

• Anticoagulant overdose

• GI bleeding (e.g., stomach ulcerations)

How quickly can arterial bleeding lead to death?

• Adults: as little as 1–2 minutes

• Infants/children: seconds

What is the immediate treatment priority in emergency transfusion situations?

STOP THE BLEEDING

What was the old practice for treating hemorrhaging trauma patients?

Infuse osmotic-balanced clear fluids (crystalloids/colloids) until blood products arrived

• problem: do not remain intravascular, move into tissues, and cause severe edema

What is the guiding principle of current trauma resuscitation?

The less clear fluid given, the better the outcome

What is the preferred product in current trauma treatment?

LTOWB (Low-Titer O Whole Blood)

Which plasma types are used as osmotic-balanced fluids in trauma?

FFP, thawed plasma, and liquid plasma

Which plasma can be used for patients with unknown ABO type?

Group A plasma

Are cold-stored platelets used in trauma care?

Yes, if available, often en route to the hospital

What protocol is used for massive bleeding or hemorrhaging?

Massive Transfusion Protocol (MTP)

In what situations is MTP most commonly activated?

Trauma cases and certain major surgical procedures

What transfusion ratio is maintained during MTP?

1 : 1 : 1
- RBCs : Plasma : Platelets

techniques to deliver care w/o violating religious traditions

• EPO: hormone creates RBCs

• vitamims: Vitamin K that helps with blood clots

• harmonic scapel: which cuts and cauterizes at the same time

• intraoperative blood salvage system : recovers blood from operating tables, washes it, returns cleaned blood to patient

• artificial Hb: mimic human hb and studied for use in transfusions

What is meant by artificial blood?

Substances designed to carry and deliver oxygen without using human RBCs

types: Perflurocarbons (PFCs), Haemoglobin based products (HBOCs)

What are Hemoglobin-Based Oxygen Carriers (HBOCs)?

derived from animal (bovine) sources or artificially recombinant technology

Has any artificial blood been FDA approved?

No

What are major safety concerns with artificial blood products?

• Adverse effects and toxicity

• inefficient oxygen delivery in microvasculature

• retention of PFC compound in liver

• cannot mimic blood & its properties (plts, coag)

What does leuko-reduced blood help reduce?

• Febrile transfusion reactions

• HLA antibody alloimmunization

What does CMV-negative blood help prevent?

Cytomegalovirus (CMV) infection, which can be fatal in neonates

What is the purpose of irradiating blood products?

To prevent Transfusion-Associated Graft-vs-Host Disease (TA-GVHD)

Why does TA-GVHD occur in immunocompromised patients?

The patient cannot suppress transfused donor T-cells, which become activated and attack host tissues

• severe organ damage/rejection, often fatal

Who is considered immunocompromised and requires irradiated blood?

• Cancer patients receiving massive chemotherapy

• Patients with immune diseases/conditions

• Neonates

Why is irradiation especially important for directed (family) donor blood?

Family donors share HLA similarities, increasing TA-GVHD risk

How does irradiation affect RBC integrity?

It weakens the RBC membrane

What substances leak from irradiated RBCs during storage?

Potassium (K⁺) and free hemoglobin

key characteristics of irradiated blood products?

• Performed using a lead-shielded irradiator, most commonly cesium-137 (gamma irradiation)

• Dose requirement: ≥ 25 Gy to the center of the unit and ≥ 15 Gy to all other parts

• Irradiator indicator must confirm irradiation

• RBC expiration changes to 28 days from the date of irradiation